MacConkey-NPS

MacConkey-NPS are used for the detection and isolation of coliform bacteria in water, food and biological specimens. The formulation is slightly selective and corresponds to the medium recommended by the World Health Organization (1963) for the bacteriological examination of drinking water. Gram positive bacteria are inhibited by bile salts and crystal violet, whereas gram-negative organisms show good growth. Bacteria that are able to metabolize Lactose grow in pink to red colored colonies due to their ability of forming acid and the pH indicator neutral red. Bacteria not metabolizing lactose will grow colorless. The medium is manufactured and quality tested in compliance with ISO 11133:2014 standard.